Remove Unicode characters from README.md

Unfortunately for dear ole' Ionut, Berkshelf cannot handle
uploading cookbooks with files that contain Unicode characters.
When uploading, you get the following error:

Change-Id: I2c37a2761c25139bc44006cc0e5b13adf6413dd5
STDERR: ERROR: Encoding::InvalidByteSequenceError: "\xC8" on US-ASCII